This is the 9748th most frequent Turkish word.
arkalığı
The Turkish word "arkalığı" means "backrest" in English.
In this sentence, 'arkalığı' is used to refer to the physical backrest of a chair.
Koltukların arkalıkları rahat görünüyor.
The backrests of the chairs look comfortable.
In this context, 'arkalığı' is metaphorically used to denote support or foundation for an idea.
Bu fikrin arkalığı olarak başka bir öneri düşündüm.
As a backbone for this idea, I thought of another suggestion.
Here, 'arkalığı' refers to the rear part of the bookshelf as a structural component.